title: Effectiveness of hepatic arterial embolization on radiofrequency ablation volume in a swine model: relationship to portal venous flow and liver parenchymal pressure.
abstract: OBJECTIVE
  To evaluate the effectiveness of transcatheter arterial embolization (TAE) on radiofrequency (RF) ablation volume and compare portal vein (PV) flow and liver parenchymal pressure before and after treatment.
  
  
  METHODS
  Eight healthy female swine were divided into four groups to be treated with RF ablation alone (RF-only group), RF ablation after TAE with gelatin sponge particles (GSPs; RF/TAE group), RF ablation after TAE with Lipiodol plus GSPs (RF/TAE/Lipiodol group), and PV embolization (PVE) with GSPs after TAE with Lipiodol plus GSPs (RF/TAE/Lipiodol/PVE group). Five ablations were created in each swine, with 10 ablations per group. A 2-cm expandable LeVeen needle electrode was used for RF ablation.
  
  
  RESULTS
  The greatest ablation volume (18,410.1 mm(3) +/- 3,986.4) was observed in the RF/TAE/Lipiodol/PVE group. Of the RF-only, RF/TAE, and RF/TAE/Lipiodol groups, the RF/TAE/Lipiodol group (14,835.5 mm(3) +/- 2,743.2) had a significantly larger ablation volume than the RF-only (8,002.6 mm(3) +/- 2,788.3) and RF/TAE groups (10,398.5 mm(3) +/- 2965.8; P < .05/3). PV pressures increased significantly after TAE (P < .01) compared with the pressure before TAE in the RF/TAE/Lipiodol and RF/TAE/Lipiodol/PVE groups, but not in the RF/TAE group. A marked increase in liver parenchymal pressure was seen during RF ablation; however, there were no significant differences among groups. Accumulation of Lipiodol was noted in the sinusoids in the RF/TAE/Lipiodol and RF/TAE/Lipiodol/PVE groups.
  
  
  CONCLUSIONS
  TAE with blockade of PV flow before RF ablation was associated with greater ablation volumes. Liver parenchymal pressure showed no correlation with increased ablation volume.
authors.affiliation: Department of Radiology, Wakayama Medical University, 811-1 Kimiidera, Wakayamashi, Wakayama 641-8510, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Iwamoto
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kawai
authors.forename: Morio
authors.initials: M
authors.lastname: Sato
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Tanihata
authors.forename: Isao
authors.initials: I
authors.lastname: Takasaka
authors.forename: Hiroki
authors.initials: H
authors.lastname: Minamiguchi
authors.forename: Shinya
authors.initials: S
authors.lastname: Sahara
authors.forename: Kouhei
authors.initials: K
authors.lastname: Nakata
authors.forename: Shintaro
authors.initials: S
authors.lastname: Shirai
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D017115:Catheter Ablation / Q000379:methods*; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006499:Hepatic Artery / Q000502:physiology*; D006801:Humans; D008099:Liver / Q000033:anatomy & histology / Q000098:blood supply / Q000502:physiology* / Q000601:surgery*; D023421:Models, Animal; D011169:Portal Vein / Q000502:physiology*; D013552:Swine; D016896:Treatment Outcome